Collating and binding systems for saddle stitchers are well known in the printing industry for mass producing booklets, catalogues, magazines and the like. Typically, one or more sharply folded and generally pre-printed blanks or signatures are selectively and sequentially fed by a number of spaced signature feeders. The signatures are delivered such that the folded margins or spines of the signatures come to rest upon a collating conveyor line or chain which travels past the signature feeders. The conveyor gathers the signatures, one on top of the other, and moves them through one or more on-line printing stations to a stitching or binding station. The assembled signatures are then usually diverted to a trimming station and further led to an addressing station where mailing information is applied. Thereafter, the assembled and addressed signatures are sorted, bundled and readied for mailing or distribution.
Prior art systems of this type contemplate the computer controlled production of various demographic editions of books or catalogues of internal and external signatures containing individually tailored information or customized printing on selected signatures. In providing these demographic versions, the prior art commonly employs an information source which indicates the special interest of each subscriber within a common postal locale. Based on the information source, a controller selectively actuates the signature feeders to deliver certain signatures upon the conveyor to form one or more individualized editions of a booklet or magazine for each subscriber within the zip code area. Information in the source is generally arranged in sequential order so that the formed booklets or magazines leave the conveyor ready to be sorted into groups which qualify for postal discounts. As part of this collation process, the signatures are conveyed past one or more customizing stations typically employing ink jet printing for applying personalized data.
Ink jet printing is a non-contact marking method wherein the only element touching the material or substrate to be marked is the printing ink. The process is ideal for printing on a variety of materials at high speeds. The most important portion of the ink jet printer is the print head which is supplied with a special ink pumped from a reservoir. The ink emerges from a nozzle on the head as a stream of tiny drops of equal size broken up by ultrasonic oscillation. As the drops are formed, they pass through a charging electrode and collect a variable electrostatic charge as desired. The size of the desired charge determines the position of the drops on the substrate because they then pass through a high voltage field. This field causes each droplet to be deflected sideways by an amount proportional to the size of the desired charge. The print head produces characters from a single line of drops. Moving the substrate at right angles to their plane of deflection produces lines of characters in a dot matrix pattern. As long as the print head is disposed at the correct distance from the substrate, the ink droplets will properly deflect and yield a quality printing result. This requirement becomes even more important as the ink jet printer is called upon to deliver certain types of printing, such as bar coding, which demand meticulous accuracy in the formation of minuscule bars and half bars as used for addressing purposes in qualifying for postal discounts.
It is desirable that magazines be processed and addressed to take advantage of maximum postal discounts. For example, sorting magazines into carrier route bundles is the most cost effective method of mailing in order to qualify for the lowest possible postal rate. All remaining magazines not sorted into carrier bundles are eligible for bar code discounts as long as the address information on them is complete and accurate. In this regard, it would be advantageous if a plurality of magazines could be assembled and selectively addressed during a given production run to attain the optimum postal rate available for each sequential magazine.
Prior art systems have been lacking because of inflexibility. For instance, systems currently employed do not possess the most efficient sorting capability at their mail tables or addressing station since completed books are routed either to a reject conveyor or a stacker. There is no special provision to more perfectly sort those addressed magazines so that they can meet minimum bundle specifications for a given postal locale and still get the most favorable postal rate. Additional techniques for improving sortation options need to be considered.
Accordingly, it is desirable that the demographic bindery system offer a greater degree of customization, improving upon the print quality of assembled and addressed books and magazines of variable thickness and allowing a better sortation of assembled and addressed books and magazines to obtain optimal postal discounts.